Re: Rational PC mail , was Re: PGP on BBS

[jim@tadpole.com (Jim Thompson)]

> From: pfarrell@cs.gmu.edu (Pat Farrell)
> 
> With NUpop and Eudora, SLIP is optional. The NUpop docs say
> that SLIP slows down the transfer, and recommends simple ASCII
> async connection using a reliable modem (MNP or V42/V.42bis)

I don't understand how the authors of this document can do so.  Modern
compressed-header SLIP implementations will compress the TCP/IP/SLIP
headers down to 5 or 6 'bytes' (octets), on the average.  In theory, I
suppose its true, but in practice, it makes little difference.  Even
without header compression, and assuming minimal-sized datagrams, you
end up with an overhead of 41/576.  93% of your bandwidth is still
yours.

A simple ASCII async connection using MNP or V.42 still violates the
end-to-end argument.  Serial ports can, and do loose characters.  Leaving
your encrypted message, or even your key, to the whims of a cheap modem,
(you'll never know what the other guy has), or back serial drivers seems
a bad idea to me.

Jim